public class T19{

	public static void main(String[] args){
	
		double[] oldArr = new double[]{72,89,58,87,91,53,82,71,93,76,68,65};
		
		T19.add(oldArr);
	}
	public static void add(double[] shuZu){
		double sum = 0;
		double b = 0;
		for(int i = 0;i < shuZu.length;i++){
		
			sum = sum + shuZu[i];
			b = sum/12;
		}
		System.out.println(b);
	}
}